Sandbox c6

1ACJ shows the crystal structure of Torpedo californica acetylcholinesterase (TcAChE) complexed with tacrine.

Tacrine is a parasympathomimetic and a centrally acting cholinesterase inhibitor.

It was the first centrally-acting cholinesterase inhibitor approved for the treatment of Alzheimer's disease.

Tacrine’s ring is stacked between the aromatic rings of tryptophan 84 and phenylalanine 330

 (W84 and F330)

Harel M, Schalk I, Ehret-Sabatier L, Bouet F, Goeldner M, Hirth C, Axelsen PH, Silman I, Sussman JL. Quaternary ligand binding to aromatic residues in the active-site gorge of acetylcholinesterase. Proc Natl Acad Sci U S A. 1993 Oct 1;90(19):9031-5. PMID:8415649